Rear seal done and oil still leaking

Now I bought my car in the summer , when I was getting it checked out by my guy he told me the rear main needed to be done. I put a quart every 300miles, it’s not the end of the world but just enough to bother me .
So I’m planning to do the seal.... as I’m looking at the previous owners bills , i see that in 2015 he did the rear main by a local British garage . Do you think that this due to a faulty seal or non use of speedy. Do seals fail often ?

The O/E Moss & V.B. seal YES, are JUNK!!! Get a Gayco or the new Phonier seal, just under $20. but are the best. I would get a new ft. seal for the trans. input shaft & if it is showing any sine of oil, change it

In reply to # 3680335 by mgv8glen
The O/E Moss & V.B. seal YES, are JUNK!!! Get a Gayco or the new Phonier seal, just under $20. but are the best. I would get a new ft. seal for the trans. input shaft & if it is showing any sine of oil, change it

Before doing the rear seal again (double-)check the PCV system. One never knows whether pressure in the block does not aggreviate this problem of oil loss.
My own oil consumption has risen above yours if driving fast on the French highways (1 litre per 1200km/800 miles, it used to be 1 litre/1000 miles for a long time)

Tom G
When you have the engine back plate off the necessity will be apparent. When you do as fingernail test and you can feel a ridge left by the seal in the crankshaft time for a sleeve & seal .
These wear sleeves are available and are a SKF part.
Being a fellow Montrealaise

Glenn, Did you mean Gaco? I can't find anything close to Phonier, maybe Payen?

In reply to # 3680335 by mgv8glen
The O/E Moss & V.B. seal YES, are JUNK!!! Get a Gayco or the new Phonier seal, just under $20. but are the best. I would get a new ft. seal for the trans. input shaft & if it is showing any sine of oil, change it

The original seals (even from the factory) were not the best. Moss (and others) do offer uprated seals. The problem is exacerbated by the fact that when a crankshaft is turned (during an engine rebuild), the machinest will often skim a few thousandths off the seal surface to remove any ridge that has developed. Although this cleans up the surface, it also reduces the diameter slightly and a marginal seal may not press against the shaft with sufficient force to seal.

If you suspect your shaft has been turned (on the seal surface), OR there is any hint of wear, roughness, ridge then you need to apply a SpeediSleeve before replacing the seal again. And definitely get the uprated seal, not the standard one.

I installed a double-edged seal, can't recall the manufacturer name back in 2010 because my crank surface had a line etched in it from the previous original seal that had it on there for over a hundred thousand miles. I had to pull the engine and gearbox out a second time, because I put too much oil in my new overdrive.

Upon doing that I realized and found, that the double-edged seal had torn a little bit and was starting to leak, this was after 5 miles. So, I learned about Speedi-sleeves, and I installed one of those with a standard high quality regular rear main seal. No leaks in 8 years and it's working perfectly. If your crank surface has any kind of line etched in it from the previous seal, I highly recommend you use a speedi sleeve and then a standard high quality rear main seal.

Regardless, install a speedi sleeve, as well as a new seal. When you push the seal over the speedi sleeve make sure that you have a strip of tape covering the edge of the sleeve, otherwise it will nick the seal and you'll be back at square one. Also the sleeve can be fitted without removing the back plate.

Did my rear main seal last fall and I found that was only half of the leak. The rear plate gasket wasn't installed right. I'm not a fan of a lot of RTV sealant but I put it on that plate gasket when I replaced it. It's just so paper thin , I don't know how it even works. I used the uprated seal and a speedy sleeve. No more leak.